package reflection;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

// 性能对比分析
public class Test10 {
    public static void main(String[] args) throws ClassNotFoundException, NoSuchMethodException, IllegalAccessException, InvocationTargetException {
        test01();
        test02();
        test03();
    }

    // 普通方式
    public static void test01() {
        User user = new User();
        long startTime = System.currentTimeMillis();
        for (int i = 0; i < 1000000000; i++) {
            user.getName();
        }
        long endTime = System.currentTimeMillis();
        System.out.println("普通方式调用十亿次方法耗时：" + (endTime - startTime) + "ms");

    }

    // 反射方式。不关闭安全检测
    public static void test02() throws ClassNotFoundException, NoSuchMethodException, InvocationTargetException, IllegalAccessException {
        User user = new User();
        Class<? extends User> userClass = user.getClass();
        Method getName = userClass.getMethod("getName");
        long startTime = System.currentTimeMillis();
        for (int i = 0; i < 1000000000; i++) {
            getName.invoke(user);
        }
        long endTime = System.currentTimeMillis();
        System.out.println("反射方式调用十亿次方法耗时：" + (endTime - startTime) + "ms");

    }

    // 反射方式。关闭安全检测
    public static void test03() throws ClassNotFoundException, NoSuchMethodException, InvocationTargetException, IllegalAccessException {
        User user = new User();
        Class<? extends User> userClass = user.getClass();
        Method getName = userClass.getMethod("getName");
        getName.setAccessible(true);
        long startTime = System.currentTimeMillis();
        for (int i = 0; i < 1000000000; i++) {
            getName.invoke(user);
        }
        long endTime = System.currentTimeMillis();
        System.out.println("关闭安全检测调用十亿次方法耗时：" + (endTime - startTime) + "ms");

    }

}
